The 2-unit, 1,540-megawatt Four Corners Power Plant, located on the Navajo Indian Reservation west of Farmington, New Mexico, is operated by APS. Fueled by low-sulfur coal from the nearby Navajo mine and cooled by the nearby Morgan Lake, the plant is owned by APS and 4 other utilities in the Southwest. APS' stake in Four Corners makes 970 megawatts of energy available to the APS system.

About 80% of the employees at the plant are Native American.

Cholla

The 995-megawatt Cholla Power Plant is located in northeastern Arizona near Holbrook. APS operates the plant and owns Units 1, 2 and 3, which are capable of producing 615 megawatts of electricity. PacifiCorp (PAC) owns the 380-megawatt Unit 4 - the largest unit at the plant. The two utilities participate in a seasonal power exchange in which PAC customers in the Pacific Northwest receive electricity from the APS system in the winter when their electricity demands are high and APS receives PAC power in the summer, during APS' peak demand.

Cholla is fueled by coal from the McKinley Mine in New Mexico.

Navajo

The Navajo Power Plant is located in northern Arizona on the Navajo Indian Reservation near Page, and features three 750-megawatt coal-fueled, steam-electric generating units. An electric railroad delivers coal to the plant from a mine on the Navajo and Hopi Indian Reservations at Black Mesa in northern Arizona.

The plant is operated by Salt River Project, and is owned by a partnership of 5 utility companies and the U. S. Bureau of Reclamation. APS owns 14% of the plant.

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natural gas operated plants

We own or operate 7 natural-gas-fueled plants in Arizona.

redhawk

Redhawk is our largest combined-cycle power plant. It includes 2 identical 530-MW natural gas-fueled combined-cycle units. Located near the Palo Verde Nuclear Generating Station west of Phoenix, Redhawk uses treated effluent purchased from Palo Verde to meet its cooling needs. Redhawk is a zero liquid discharge site; the cooling water is continually reclaimed and reused. No water is released to the environment.

The natural gas-fueled power plant has 2 steam and 2 combustion turbine units capable of generating about 340 MW. The Ocotillo Solar PV Plant is located on the grounds, as well as the offices for the APS Solar Operations and Maintenance group, which operates the APS Solar Fleet. Located in Tempe, AZ, Ocotillo also is the location for the Tempe/APS Joint Fire Training Center.

The 450-MW Sundance Generating Station in Coolidge, AZ, is the newest member of our fleet. The simple-cycle, natural gas-fueled station consists of 10 quick-start combustion turbines. We purchased the 450-MW station in Spring 2005.

saguaro

The natural gas-fueled power plant has 3 combustion turbine units with a combined capacity of about 189 MW. We own and operate all 3 generating units, located north of Tucson, AZ.

yucca

We operate the natural gas-fueled power plant near Yuma in southwestern Arizona, and own 6 combustion turbine units that produce nearly 243 MW for our customers. The plant also includes a 75 MW steam turbine, and a 20 MW combustion turbine. Imperial Irrigation District owns those 2 turbines and we operate them.

douglas

The Douglas Power Plant, located in Douglas in southeastern Arizona, has 1 16-MW combustion turbine peaking unit and is put into service only when demand for electricity is high in the Douglas area. The plant has no full-time employees but is operated and serviced by employees from the Saguaro plant, near Tucson.​

The Palo Verde Nuclear Generating Station®, located about 55 miles west of downtown Phoenix, has been the largest power producer of any kind in the United States since 1992. Its three units are capable of generating more than 4,000 megawatts of electricity.

Because of its desert location, Palo Verde is the only nuclear plant in the United States that does not sit on a large body of water. Instead, it uses treated effluent from several area municipalities to meet its cooling water needs, recycling approximately 20 billion gallons of wastewater each year.

Palo Verde, which has an economic impact of approximately $1.8 billion annually and is the largest single commercial taxpayer in Arizona, is operated by APS and is owned by a consortium of seven utilities in the Southwest. APS owns 29.1% of the plant.